Standard keyboard



FIG. 1 is a front view of a standard keyboard showing my design;

FIG. 2 is a left side view thereof;

FIG. 3 is the top view thereof;

FIG. 4 is the right side view thereof;

FIG. 5 is the rear view thereof;

FIG. 6 is the bottom view thereof; and,

FIG. 7 is perspective view thereof. 

The ornamental design for a standard keyboard, as shown and described. 